01-15-2021, 11:56 PM | #1 |
Private First Class
48
Rep 182
Posts |
Stock 2015 335i -- CEL -- 104301, 101F01 (**RESOLVED**)
Car is completely stock (48k mileage) and threw a CEL with these 2 codes in ISTA today after normal driving around town. Think it came on at engine start up.
Reset the codes. Drove to the store with no issues. Turned off engine. Shopped. Came back to car. Started engine. CEL back with the same 2 codes. DME 104301 Absolute pressure sensor, intake pipe, plausibility, after-run: Pressure too high DME 101F01 Air mass system, plausibility: calculated air masses in the air intake system not plausible Did some research and it seems like cause is undetermined. Appears mostly tuned cars are getting these codes but mine is stock. Possible charge pipe issue? Don't see or hear any leaks. Maybe I need to remove TMAP and clean? Attached screenshots of code Details & System context page from ISTA. Last edited by ctbear; 07-27-2021 at 11:02 PM.. |
01-16-2021, 03:36 PM | #2 |
Major General
4370
Rep 7,622
Posts |
Charge pipe can fail even on a stock car so i would start there. It usually cracks then blows at the top near the TB.
Also, it looks like the code is for the MAP on the CP no the one after the TB? Ive never heard of cleaning those, only the MAF. How confident are you on the cars history - any chance it had mods before? Its unlikely a stock car that has never been touched has a leak, but if was modded and reverted back to stock a leak is more likely. |
Appreciate
0
|
01-17-2021, 05:47 PM | #3 |
Second Lieutenant
95
Rep 292
Posts
Drives: 2014 335i 6MT MSport
Join Date: Mar 2015
Location: N. Fulton, GA
|
When my charge pipe blew right at the intake manifold, I had no CEL even after restarting. Seems odd that it didn't.
__________________
2014 F30 N55 6MT, gray/red, M-sport, VMR 710/Mich PS 4S, MPPK, MPE 2001 E53 M54 5MT peeling green/black, well-optioned |
Appreciate
0
|
01-17-2021, 08:16 PM | #4 |
Private First Class
48
Rep 182
Posts |
I inspected the entire air intake line (from above and below) starting from the air filter box and couldn't find any leak (had someone revving inside the vehicle as well). I went ahead and removed the MAF and MAP to clean (they did not appear to be dirty). Vacuumed the engine air filter a little (new one on order). So far the codes have not returned this time since I've reset them after performing these tasks.
I did notice there was a little bit of oily residue on the bottom side of the charge pipe where it connects to the throttle body. Looks like it's residue from blowby. I inserted my boroscope through the MAP hole on the chargepipe to inspect the inside of the charge pipe and the throttle body, which looked surprisingly clean to me. Barely any carbon or residue build up. No visible crack or breakage on the chargepipe. I am absolutely confident that this car has remained stock its entire life as I purchased it as a CPO with barely 30k miles from the 1st owner: late middle aged Asian mom Here's a picture from below looking up at the bottom side of the chargepipe to throttle body connection. Note the blowby residue. Last edited by ctbear; 01-17-2021 at 08:21 PM.. |
Appreciate
0
|
01-17-2021, 08:54 PM | #5 |
Captain
224
Rep 834
Posts
Drives: Bmw 335i f30 N55 ( sold)
Join Date: Nov 2017
Location: Venice Florida
|
Check your intake inlet. The part that connects from the intake down into the turbo.. mine cracked on a stock car and it threw a code.
I also had charge pipe blow off on stock car.
__________________
2012 bmw 335i sedan
VRSF catless DP VRSF 5? HD IC Stock intake(had open before and was sick of noise) BMS CP 550i 351m rims with 275/245 set up. No tune as of yet. |
Appreciate
0
|
01-19-2021, 12:15 AM | #6 | |
Private First Class
48
Rep 182
Posts |
Quote:
I will check that portion more carefully. Didn't notice anything the first time I checked. Same codes came back today after some driving |
|
Appreciate
0
|
01-19-2021, 11:26 AM | #7 | |
Major General
4370
Rep 7,622
Posts |
Quote:
|
|
Appreciate
0
|
07-26-2021, 01:03 PM | #8 |
Enlisted Member
8
Rep 33
Posts |
Also had 101F01 after VVT motor and ecc shaft replacement
Solution: my mechanic replaced the boost solenoid and so far so good! He also found a boost leak on the inlet pipe (MST hose from turbo to intake tube) as well as a fucking ziptie holding the charge pipe to the FMIC from the wack mechanic who worked on my car before the current mechanic (shoutout to Kings Automotive in Bloomingdale, NJ). He reset adaptations for me several times, wasnt going away. Did a smoke test and fixed said boost leaks. Installed new boost solenoid and so far no problems. |
Appreciate
0
|
07-26-2021, 10:45 PM | #9 |
Private First Class
48
Rep 182
Posts |
UPDATE:
There was no boost leak. The issue is with a "dirty" intake manifold pressure sensor (the one after the throttle body) not the pressure sensor on the charge pipe (boost/charging pressure sensor). I simply cleaned the sensor off with some crc maf cleaner to resolve the problem. It took me a while, but I finally found the time and figured out how to fully take advantage of and utilize ISTA to properly diagnose the issue to resolve this. Pre cleaning - live ISTA sensor feeds showed intake pressure sensor deviating by +/-2.2 hPa Post cleaning - live ISTA sensor feed shows identical readings from all 3 pressure sensors: intake (manifold) pressure sensor, ambient pressure sensor, charging (boost) pressure sensor. Take away: routine pressure sensor cleanings may help Last edited by ctbear; 07-27-2021 at 11:01 PM.. |
Appreciate
1
F32Fleet3606.00 |
11-27-2021, 04:37 AM | #10 | |
New Member
2
Rep 23
Posts |
Quote:
|
|
Appreciate
0
|
11-27-2021, 11:38 PM | #11 | |
Private First Class
48
Rep 182
Posts |
Quote:
Then expand the tree for Engine, intake, intake pipe pressure. You can then run the test plan for the intake pipe pressure which will display all 3 sensor readings. |
|
Appreciate
0
|
11-28-2021, 01:41 AM | #12 | |
New Member
2
Rep 23
Posts |
Quote:
Thank you. |
|
Appreciate
0
|
11-29-2021, 12:46 AM | #13 | |
New Member
2
Rep 23
Posts |
Quote:
Unfortunately I had already cleaned the sensors beforehand so didn't have a before set of values to compare but went ahead and setup ISTA and did a check of the MAP sensors (after cleaning) and found that the charge pressure sensor was varying +/- 1.5 hpa (1029 to 1033 hpa) whereas the manifold and ambient pressure sensor where dead steady at 1030 hpa with no variation. Does this mean that the charge pressure sensor is on its way out? Is it worthwhile to replace it with a new one? Car has done 75K kilometers to date. |
|
Appreciate
0
|
11-30-2021, 09:08 PM | #14 | |
Private First Class
48
Rep 182
Posts |
Quote:
Are you still receiving the check engine code? +/- 1.5 hpa should not trip the code as it is within the allowable tolerance range. My problematic sensor also behaved similarly with fluctuations, which improved enough after cleaning as to not trip the code. However, my ocd got the best of me and I ended up replacing the sensor a couple months after cleaning, which resulted in a marked improvement in engine idle smoothness and a definite improvement in fuel consumption. I prefer to keep my cars as close to factory spec as possible. The decision is up to you. |
|
Appreciate
0
|
12-01-2021, 02:46 AM | #15 | |
New Member
2
Rep 23
Posts |
Quote:
|
|
Appreciate
0
|
12-02-2021, 02:24 AM | #16 | |
Private First Class
48
Rep 182
Posts |
Quote:
|
|
Appreciate
0
|
12-11-2021, 09:54 PM | #17 | |
New Member
2
Rep 23
Posts |
Quote:
Hi, I replaced the sensor and although it gave a stable reading according to ISTA it did not fix the problem. I did another visual inspection of the intake and crankcase ventilation systems and found no visible cracks or leaks and then did a test of the pcv. I connected a pipe to the pcv valve nipple and dipped the end into a small bottle containing some oil. Started the engine at cold and initially did not see any suction of the oil but within 10-20 seconds (after the idle started to come down) the oil was being sucked up the pipe to a height of about 15-20cm and held at that level so I assume that there was some vacuum had been generated at the pcv for a short period of time during that startup process. I re tested after the idle had settled down to normal (650rpm) by disconnecting the pipe, reattaching it and the oil was slowly being sucked to a height of about 5cm so the vacuum had dropped but was still present. I think there is a small leak in the pcv although I still don't understand why it is worse at cold start (fault code 101F01 & 118001) and not during normal operation. There are no oil leaks around the VC so I think it's just the pcv diaphragm which has a small tear. Can anyone confirm that the PCV should not have any vacuum at the nipple at any time? From what I read online one side of the valve is open to atmosphere so that when a vacuum is created by engine on the other side, the diaphragm closes against the internal spring and closes (or opens)? a valve to divert oil vapour into the turbo inlet pipe. Want to confirm before I go ahead and order an new VC. Thanks. Last edited by audi01; 12-11-2021 at 10:08 PM.. |
|
Appreciate
0
|
12-12-2021, 12:56 AM | #18 | |
Private First Class
48
Rep 182
Posts |
Quote:
Refer to 8:00 mark in this video: The TEST plan will evaluate all codes and walk you through it step by step starting with what is most likely to least likely cause of the codes. |
|
Appreciate
0
|
12-12-2021, 01:07 AM | #19 |
New Member
2
Rep 23
Posts |
Hi, Yes, I did look at the test plan but I don't have a smoke tester which is needed to do a leak test on the air intake and crankcase ventilation system. The test is looking for leaks which would cause the increase in air after the MAF. Decided to check the PCV as it seem to be a common fault which causes the same problem (vacuum leak in the crankcase ventilation system). Some videos on YT suggested using a flame to show the vacuum and there was mention of using a pipe and oil but I didn't see any videos show that test. Went ahead and did it myself and did verify that I was getting a vacuum leak (I think) from the PCV during the cold start. I assume that the leak is very small at the moment as I have only started noticing this problem (rough cold start) and don't get the more severe symptoms (rough idle all the time or squealing from from the front/rear main seals).
Last edited by audi01; 12-12-2021 at 06:07 AM.. |
Appreciate
0
|
12-24-2021, 05:10 AM | #21 |
New Member
2
Rep 23
Posts |
Replaced the VC and unfortunately no fix to the cold start problem. Idle once warm is a little smoother and I did find that the VC gasket was brittle and cracked but I think I replaced the VC a little too early. Have decided to do a smoke test and have ordered a smoke tester (probably should have done this first). Did a bit more research and think the problem occurs when the DME switches from the open loop start to the closed loop stage after the initial warm up of the Cats. At cold start the DME runs a open loop fuel map and just runs rich without using the O2 sensors to adjust A/F. Then once the Cats have warmed up a bit, it switches to the closed loop stage and tries to adjust the A/F using sensor data (O2, MAP and MAF?). A vacuum leak could cause the lean fault codes I get during this stage as it would mess with the measurements the DME is reading to adjust A/F. Still not sure why this problem is temperature related though.
|
Appreciate
0
|
12-24-2021, 02:36 PM | #22 |
Private First Class
48
Rep 182
Posts |
Thanks for the update. Sorry to hear about that buddy. I can understand the frustration. I am aware that a lot of owners experience a slightly rough cold start (lasts less than a minute) (some vibrations/shaking/rocking) before it smooths out. It seems like a weird quirk that's accentuated by winter weather for the N55.
Is 101F01 the only persistent code at this point? Happy holidays and good luck with the car. |
Appreciate
0
|
Post Reply |
Bookmarks |
Tags |
101f01, 104301 |
|
|